The present invention relates to a dishwasher and, more particularly, to a steam generating structure in a dishwasher.
A dishwasher including a steam washing step or a steam softening step is proposed in copending application, STEAM WASHING IN A DISHWASHER, Ser. No. 973,917, filed on Dec. 28, 1978 by Ichiro Oguri and Yoshihiro Koyama and assigned to the same assignee as the present application.
The present invention is to improve the steam generating means in a dishwasher such as disclosed in the above-mentioned application Ser. No. 973,917.
Accordingly, an object of the present invention is to improve a steam generating heater means in a dishwasher.
Another object of the present invention is to provide a heater means which functions to generate steam in a steam softening step and to warm up the water in a main washing step in a dishwasher.
Still another object of the present invention is to provide a novel heater cover for ensuring effective steam generation and also ensuring effective warming up of the water in a dishwasher.
Other objects and further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
To achieve the above objects, pursuant to an embodiment of the present invention, an immersion heater is disposed in a lower section of a dishwashing tub. A square shaped heater cover is provided to surround the immersion heater. The bottom free end of the heater cover functions to communicate the immersion heater with the dishwashing tub. The upper free end of the heater cover is covered by a filter.
A circulation pump is provided for selectively circulating the water within the dishwashing tub and emitting the water from a sprinkler. When the circulation pump and the immersion heater are energized, the water contained in the lower section of the dishwashing tub is forced to travel through the immersion heater and, therefore, the warm water is emitted from the sprinkler. When only the immersion heater is energized, the water disposed in the heater cover is heated up and, therefore, steam is generated through the filter which covers the upper free end of the heater cover.
In a preferred form, an overheat preventing sensor is disposed in the heater cover to ensure stable operation.